Selective Laser Melting

A miniaturized selective laser melting (miniSLM) device was developed to perform operando X-ray diffraction and imaging experiments at the Swiss Light Source.  The device exhibits the full functionality of a commercial SLM device.

3D rendered view of the miniaturized SLM machine

A collimated infrared laser beam is deflected by a 2-axis scanning unit into the main chamber. The laser beam is focused onto a 12 × 12 mm2 build stage that can be translated vertically with a travel range of 12 mm and sub-micron step size. The build stage can be heated using a silicon-nitride resistive heater. Powder recoating is based on a hopper feeding system. The powder reservoir can be moved across the baseplate with the aid of a motor-spindle assembly. The device is completely closed, preventing laser light or particles to escape. The chamber is continuously flushed with high purity argon gas. With the aid of manual flowmeters, a slight overpressure is created in the chamber to avoid oxygen contamination by the outside atmosphere. The whole setup (laser, scanning unit and printing chamber) is cooled down with a closed-loop air-water exchange based chiller.  The video below describes the basic principle behind  operando X-ray diffraction during SLM. 

Laser    
  Type redPOWER® continuous wave Fiber Laser
  Wavelength 1070nm
  Maximum power 500W
Device    
  Dimensions 15mm x 20mm x 30mm
  Build plate 12mm x 12mm
  Maximum build height 8mm
  Maximum temperature 150°C
  Maximum angle tilt stage 20°

 

Operando X-ray diffraction during laser 3D printing
Samy Hocine, Helena Van Swygenhoven, Steven Van Petegem, Cynthia Sin Ting Chang, Tuerdi Maimaitiyili, Gemma Tinti, Dario Ferreira Sanchez, Daniel Grolimund, Nicola Casati
Materials Today, in press
 
Basic principle of operando X-ray diffraction during selective laser melting.